Mrs. Clinton, meanwhile, had big advantages over Mr. Sanders on the issues of terrorism and gun policy, and a narrow edge on health care.

Eighty-five percent said Mr. Sanders understands them and people like them, compared to 65 percent who said the same of Mrs. Clinton. And 57 percent said that as president, Mrs. Clinton would ultimately do what big donors want, compared to 43 percent who said she would do what regular people want.

Ninety-one percent said Mr. Sanders would do what regular people want, compared to 9 percent who said he would do what big donors want; Mr. Sanders has relentlessly hammered Wall Street and the influence of money in politics during his campaign.

Part of Mrs. Clinton’s recent pitch to Democratic voters has been that Mr. Sanders‘ plans for things like universal health care are too unrealistic to pan out in the real world. Seventy-six percent said Mrs. Clinton’s policy proposals are realistic, compared to 24 percent who said idealistic. That’s compared to 62 percent who said Mr. Sanders‘ proposals were idealistic, compared to 38 percent who said realistic.

About six in 10 voters said both Mr. Sanders and Mrs. Clinton have made fair points in their criticisms of one another.